Tony, I used to have one. As I recall, I used about 1/4 peat moss for moisture retention and 3/4 topsoil. It doesn't hurt to mix in some manure as long as it isn't too green. Put the worms in, lay newspapers on top of the dirt, and stand back. They are prolific.
BTW, don't buy that junk about letting them dispose of your household garbage. Thats a good way to have a maggot farm. Its ok to toss coffee grounds, corn meal and stuff lie that in. Put it in rows. They will eat it and also the moistened newspaper. Put a lid on it to keep vermin, varmits and cats with bowel problems out. Keep them semi-moist.
